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Section of Snoqualmie Valley Trail to temporarily close for flood-protection work


Flooding during last winter's record wet weather delayed completion of an important public-safety project along the Snoqualmie River, and now crews are preparing to finish their work to the Sinnema Quaale revetment - which means a temporary closure to a portion of the Snoqualmie Valley Trail.


King County’s Snoqualmie Valley Trail, in the Stillwater area between Duvall and Carnation, will be closed to foot and bicycle traffic from July 5 to Aug. 12, as workers complete the Sinnema Quaale Revetment reconstruction project along the Snoqualmie River.

From approximately 1-½ miles south of Northeast 124th Street to 2 miles north of the Stillwater Natural Area, the trail will be closed to all use with no detour available. Trail users are encouraged to take advantage of other portions of King County Parks’ 175-mile regional trail system.

Last winter’s record wet weather and multiple flood events delayed the completion of the Sinnema Quaale revetment project, and resulted in this summer’s short period of construction to complete the work. Due to work being done in the water, construction is constricted to summer months when protected fish species are not present.

Construction activities will include repaving State Route 203 near the project site, guardrail repairs, trail resurfacing, installing fencing along the trail, and replanting the construction site.

The construction area, known as “Car Body Curve,” sustained significant damage during severe flooding in November 2006, with further damaged caused during subsequent floods over several years.

Work that began in 2015 and was completed earlier this year included improving protection for the state highway, regional trail and a regional fiber optic trunk line, and removing the remains of at least 20 rusted 1940s car bodies that several decades ago were placed along the river to curb bank erosion.

The 31-½-mile-long Snoqualmie Valley Trail is managed by King County Parks and meanders past working farms as well as preserved open space areas, and connects to the cross-state John Wayne Pioneer Trail in Iron Horse State Park. Points of interest include Tolt-MacDonald Park, Meadowbrook Farm, Three Forks Natural Area and the Tokul Trestle.

To receive announcements about temporary trail openings or early completion, sign up for project updates on the Sinnema Quaale web page, found at


The King County Flood Control District is a special purpose government created to provide funding and policy oversight for flood protection projects and programs in King County.  The Flood Control District’s Board is composed of the members of the King County Council. The Water and Land Resources Division of the King County Department of Natural Resources and Parks develops and implements the approved flood protection projects and programs. Information is available at